U.S. Pat. No. 4,394,496 discloses triglycidyl ethers of 1,1,1-tri(hydroxyphenyl) alkanes and oligomeric reaction products of the ethers with the triphenols. These epoxides have superior high temperature properties, excellent mechanical properties, and good moisture resistance. They are of considerable interest for aerospace applications. The subject epoxides of the greatest interest are 1,1,1-tri(glycidyloxyphenyl) methanes (as such or as oligomers, i.e. advancement products). The benzene rings may include up to two bromine or choro groups each and, when this option is exercized, the epoxides would be expected to have enhanced flame retardance. Although surprisingly flexible for resins with high heat distortion temperatures, the epoxides are not as tough (impact resistant) as is desirable for certain applications, such as carbon-reinforced composites for advanced air frames.
U.S. Pat. No. 4,550,129 discloses compositions of tri(glycidyloxyphenyl) methanes with a toughnessimparting resin which is a polybrominated epoxide suoh as the diglycidyl ether of tetrabromobisphenol A. These compositions have improved flame retardancy but the carbon-bromine bonds tend to be cleaved at elevated service temperatures.
High moisture resistance is critical to the retention of physical properties in the resinous components in composite structures employed in high performance aircraft. It is known that fluorocarbons of high fluorine contents are generally hydrophobic.
Tris(pentafluorophenyl)methane (m.r. 158.degree.-159.degree. C.) has been known since it was described in 1967 by R. Filler et al. in J. Am. Chem. Soc., 89, p. 1026. Hexafluoropropylene oxide has been known since at least as early as 1952, when its preparation by electrochemical oxidation of epichlorohydridin was disclosed in British Patent No. 672,720 by E. Kauk and J. Simons. However, it has not been proposed to prepare fluorinated triphenyl methanes substituted with fluorinated (or unfluorinated) glycidyl or glycidyloxy groups. In fact, to the best of the present inventors' knowledge, incorporation of fluorine in triphenylmethane-based tris-epoxides has not even been contemplated.